Telkom nothing but the ****mes

I sign a contract with Telkom in 2018 febuary Valentine special WiFi of 30 G for R200 per month .i only recieve 30 G for the first month and after i don't know my data doesn't last four weeks it only two weeks but they says its 30G and i only use my phone normal i always at work and i can't carry my Wi-Fi coz its huge i can't put inside my bag .and fun they always send the statement its written is 10G ,5 night 5 day i don't understand and i can't reach them when i tried to call but i did email them but they did respond.